Comment 19 for bug 1904737

I think the idea makes sense. Upon reading the code, some areas to poke at are:

- The cp_available_by_circ_lib_idx index on asset.copy is a partial index on statuses 0 and 7; would be good to see if it actually matters for the relevant queries
- The action.copy_related_hold_stats() stored function also hard-codes 0, 7 and 12 (the new reserves status); this affects hold ratio calculations when applying hold policies
- Likewise for asset.staff_lasso_record_copy_count() and asset.staff_ou_metarecord_copy_count() and their counts of items available to fill hold requests
- The ahopl IDL view - this is no longer used for the pull list, but theoretically could be used by some for reporting
- eg-holds-grids hard-codes a default grid filter and cp.status 0 and 7

I think these mostly amount to details to fill in as opposed to anything fatal to the proposed patch, though it also suggests to me that (separately) that the Reserves item status should have its magic made a bit more explicit.